Hack saw frame



March 26, 1935. F. H. KELLEY HACK SAW FRAME' Filed May 29, 1954 I \nv enTbr. Y

ATTys.

Frederick H. Ke\ \e byMMkf Patented Mar. 26, 1935 UNITED STATES PATENTorncs l Application May. 29,1934. Serial No. 728,033

1 Claim.

This invention relates to hack saw frames and and has for its object toprovide a novel hack saw frame which is inexpensive to manufacture,which is constructed so that the saw blade can 5. bequickly and easilyinstalled in the frame or removed therefrom and which is further soconstructed as to hold the saw blade under the proper amount of tension.

In order to give an understanding of the invention I have illustrated inthe drawing a selected embodiment thereof which will now be describedafter which the novel features will be pointed out in the appendedclaim.

Fig. 1 is a side view of a hack saw frame embodying the invention;

Fig. 2 is a fragmentary view showing a portion of the blade-carrying armand the blade-locking member;

Fig. 3 is a section on the line 3--3, Fig. 1 with parts broken out;

Fig. 4 is a section on the line 44, Fig. 1;

Fig. 5 is a section on the line 5--5, Fig. 1.

My improved hack saw frame, which is indicated generally at 1, is madefrom a length or strip of material which is bent to form the backportion 2 of the frame, a blade-carrying arm 3 extending laterally fromone end of the back portion, and a handle portion 4 extending laterallyfrom the other end of the back portion. The handle portion 4 isconsiderably longer than the blade-carrying arm 3 and the end of saidhandle portion is bent into a U shape as indicated at 5 so that the arm6 of the U is directed backwardly toward the back 2.

The extremity of the arm 6 is provided with a pin or projection 7adapted to enter the usual aperture in one end of the saw blade 8. Theother end of the saw blade 8 is attached to the end of theblade-carrying arm 3 in such a way that when the blade is installed inthe frame the frame will be flexed slightly and the arm 3 and handleportion 4 will be drawn together slightly from their normal position.The frame 2 has some resiliency and because of the flexed condition ofthe frame the resiliency thereof serves to hold the blade 8 taut andunder the proper degree of tension.

The handle portion 4 is provided with a han dle grip 9 of wood or othersuitable material which encloses the portion 4 of the frame and providesa convenient hand hold to grasp in the hand. This handle grip may bemade of wood or any other material and is shown as having a groove 10 inwhich; the portion 4 of the-frame is received. This portion 4 may beretained the groove in any suitable way-and as one simple andinexpensive buteffective way I have-,,i1lu s trated a plurality ofstaples 11 whichare. driven into the handle in such a position thattheglegs of the stapl s will cross the groove 10 front of the portion 4.Any other way of locking the handle portion 4 in the handle grip mightbe employed, however, without departing from the invention.

The end of the saw'blade 8 is detachably secured to the end of theblade-carrying arm 3 by a simple means which is constructed so that theattachment and removal of the blade can be very easily and quicklyaccomplished.

Pivoted at 12 to the end of the blade-carrying arm 3 is a lever arm 13which is provided with a laterally-extending pin 14 to which the sawblade 8 is secured, said pin being of a size to be inserted through theusual aperture with which the hack saw blades are provided.

The lever arm 13 is adapted to be swung from its operative position inwhich it is folded against the arm 3 to its open position shown indotted lines Fig. 1. When the saw blade is to be installed in the framethe member 13 will be swung into its open position and one end of thesaw blade 8 will be attached to the arm 6 of the handle portion byinserting the pin 7 through the aperture in the end of the saw blade andthe other end of the saw blade will be attached to the swinging member13 by inserting the pin 14 through the aperture in said other end. Thelever arm 13 is then swung from its open dotted line position into itsclosed operative position shown in full lines.

The arm 13 is preferably U shape in cross section and when it is inoperative position the U shape of said lever arm embraces the arm 3.

The pin 14 extends across the channel of the lever arm 13 and the lowerend of the frame arm 3 is cut away as shown at 15 to accommodate saidpin 14 when the lever arm 13 is in its operative position. During theswinging movement of the member 13 from its open to its closed positionthe pin 14 swings about the pivot 12 as a center and because the sawblade 8 is attached to the two pins 7 and 14 the movement of the pin 14in its arcuate path will cause the arm 3 and the handle portion to bedrawn together slightly thereby flexing the saw frame. The yielding orflexing movement of the saw frame may take place in either the arm 3 orin the handle portion 4 or in both parts of the saw frame.

The swinging movement of the arm 13 from its open to its closed positioncarries the pin 14 from one side to the other of the center line of thepivot 12 and the pin 7. As soon as the pin 14 passes this center linethen the resiliency of the frame tends to complete the swinging movementof the member 13 and to fold it against the arm 3.

The relation between the length of the saw blade 8 and the normaldistance between the arms 3 and 6 is such that when the saw blade isinstalled in the frame and the lever arm 13 is in its operative positionthe frame will still be slightly flexed thereby applying a tension onthe saw blade which will hold it taut. This tension locks the lever arm13 in its operative position so that said arm will not be accidentallyswung into its open position when the saw is being used.

The installing of the blade in the arm, there-' fore, involves simplyswinging the lever arm 13 into its open position, applying the saw bladeto the pins 7 and 14 and then swinging the lever arm 13 back into itsoperative position.

The handle portion 4 is longer than the bladesupporting arm 3 so that ifthe line occupied by the saw blade were extended it would cut the handlegrip at its intermediate portion. This is an advantage because the poweror force employed in manually operating the saw is applied to the handlegrip substantially in the line of the saw blade. This makes a frame inwhich the power is most efiectively applied.

I claim:

A hack saw comprising a frame presenting a back portion, ablade-carrying arm extending laterally from the back portion at one endthereof, a handle portion of greater length than said arm extendinglaterally from the back portion at the other end thereof, the end of thehandle portion being bent into a U shape, a saw blade having one endattached directly to the U end of the handle portion and the other endattached to the blade-carrying arm, a handle grip of wood having a slotin which the laterally-extending part of the handle portion is received,said slot having a greater depth than the width of said handle portion,and fastening devices driven into the handle grip on the inside of thehandle portion, said fastening devices extending across the slot andlocking the handle grip to the handle portion.

FREDERICK H. KELLEY.

